1. Field of the Invention
The present invention relates to a developer material container, an image forming unit, and an image forming apparatus.
2. Description of the Related Art
Among conventional image forming apparatuses are electrophotographic printers, copying machines, facsimile machines, and multi function peripheral (MFP) devices capable of various tasks such as printing, faxing, and copying. For example, a printer includes image forming units each of which includes, for example, a photoconductive drum, a charging unit, an exposing unit, and a developing unit. The charging unit charges the surface of the photoconductive drum uniformly. The exposing unit includes an LED print head that illuminates the charged surface of the photoconductive drum to form an electrostatic latent image. The developing unit develops the electrostatic latent image with toner into a toner image. A transfer roller transfers the toner image onto paper. Then, a fixing unit fixes the toner image on the paper into a permanent image.
A toner cartridge serves as a developer material container and is detachably attached to the image forming unit. The developing unit has a toner receiving opening formed therein. The toner cartridge has a toner outlet formed in its bottom wall. The toner outlet is closed and opened with a shutter. When a user operates an operation lever of the shutter to open the shutter, the toner is discharged from the toner cartridge into the developing unit through the toner receiving opening.
A conventional toner cartridge is configured such that the shutter may be opened and closed with the toner outlet facing upward. Therefore, opening the shutter inadvertently may allow foreign matter to enter the toner cartridge.